1. Field of the Invention
The invention relates to a wave washer, a rotary shaft supporting device including the wave washer, and an electric motor including the rotary shaft supporting device.
2. Description of Related Art
Japanese Patent Application Publication No. 2009-201255 (JP 2009-201255 A) describes an electric motor that includes a wave washer located between a rolling bearing for a rotary shaft and a holding case. The wave washer applies a load to the rolling bearing.
The wave washer has such an outer diameter that a clearance is formed between the wave washer and the holding case. If the central axis of the wave washer is offset from the central axis of the rolling bearing, a non-uniform load is applied to the rolling bearing by the wave washer. Therefore, the positional offset between the wave washer and the rolling bearing should be as small as possible. Note that, any wave washers that apply loads to target members other than rolling bearings may also have a similar problem.